Generally, a vehicle is equipped with a navigation device which is able to receive signals from a plurality of satellites belonging to a GPS (Global Positioning System) for checking the current position, a moving speed, etc. or for determining a moving path, and which computes the position of a corresponding vehicle by using latitude, longitude, altitude, etc. After the above operations, a certain map data including the current position is provided to a driver. Along with its useful functions such as the current position and speed of a user and a moving path to a destination, the users of the navigation device increase day by day.
The vehicle is shipped with a navigation device generally equipped in a dashboard. Here, a relatively luxury and expensive vehicle model is inherently equipped with a navigation device. An ordinary model of a vehicle is not generally equipped with an expensive navigation device due to its higher price. In case of a built-in navigation device, the user is not able to select a desired device among various navigation devices. When it is needed to change with a new device, the navigation device installed in a previous vehicle cannot be removed and moved to a new vehicle. So, a lot of the information stored in the previous vehicle may be lost, so the user should repurchase a new navigation device and should learn the manual again concerning the new navigation device, and should input again a lot of data, which lead to many inconveniences and a lot of workload.
So, some drivers intend to separately purchase and install a certain portable terminal comprehensively having the multimedia functions such as a relatively lower price vehicle navigation device, a 3D image playback function, a music playback function, etc. Since the vehicle shipped with no navigation device is initially not provided with a certain space for installing a navigation device in the interior of a vehicle, the installation of the same is not easy, so the installed navigation device may be seen from the outside through windows, which leads to a higher robbery possibility. In order to overcome the above problems, when a user repeats an engagement and a disengagement of the device, a fixing structure of a portable terminal may be hurt.
When a portable terminal is installed in the dashboard along with many electric lines connected to the terminal or when the portable terminal is not used and so only a holder structure used for supporting the navigation device is left alone, an outer appearance looks bad due to the electric lines or the holder structure left alone.
In case of a vacuum absorption type which is widely used for engaging a navigation device on an inner surface of a windshield of a vehicle, the vacuum absorption navigation device and its holder structure are not stored in the dashboard, so that a driver's forward vision may be interfered, and when the temperature decreases in winter, an adhering force may be significantly decreased.